On the settling of small grains in dusty discs: analysis and formulas [EPA]

http://arxiv.org/abs/2004.03689


Instruments achieve sharper and finer observations of micron-in-size dust grains in the top layers of young stellar discs. To provide accurate models, we revisit the theory of dust settling for small grains, when gas stratification, dust inertia and finite correlation times for the turbulence should be handled simultaneously. We start from a balance of forces and derive distributions at steady-state. Asymptotic expansions require caution since limits do not commute. In particular, non-physical bumpy distributions appear when turbulence is purely diffusive. This excludes very short correlation times for real discs, as predicted by numerical simulations.

Read this paper on arXiv…

G. Laibe, C. Brehier and M. Lombart
Thu, 9 Apr 20
54/54

Comments: 13 pages, 4 figures, accepted for publication in MNRAS